Capillary tube blood collector



June 1, 1965 F. M. cox 3,186,236

CAPILLARY TUBE BLOOD COLLECTOR Filed Jan. 2, 1962 FREDERICK M Cox INVENTOR.

avg/M V ATTon NEVS United States Patent 3,186,236 CAPHJLARY TUBE B1001) CGLLECTOR Frederick M. Cox, 803 Montrose Ave, South Pasadena, Calif. Filed Jan. 2, 1962, Ser. No. 163,777 1 (Ilairn. (Cl. 73-4 256) This invention has to do with the collection of blood samples from patients by nurses and technicians or the like for laboratory tests and with instruments for collecting such samples.

In recent years the science of blood chemistry has developed to the point where many tests can be made from very small quantities of blood. Thus it becomes unnecessary to withdraw blood from a vein of the patient and a simple needle prick of the skin rendering only a small drop or droplet of blood supplies sufiicient blood for the purpose. However, since the test tube or centrifuge tube in which the blood must be placed for testing is small, it is difficult to collect the blood therein, that is, it is difficult to transfer the blood from the patients skin to the interior of the tube, particularly with instruments now available.

An object of the invention is to provide novel and improved means for collecting in a small test tube or centrifuge tube a sample or quantity of blood from the surface of the skin of a patient or from another source.

More particularly it is an object to provide means for collecting small or minute quantities of blood samples in a small test tube or container utilizing a capillary tube and to provide a novel fitting for a container in which the blood is to be collected which releasably receives the capillary tube and enables the application of suction or reduction of pressure within the test tube or container to cause the blood to flow through the capillary tube into the container or test tube.

Another object is to provide a new and. improved fitting which is particularly adapted for temporarily substantially closing the open end of a test tube or the like and providing a restricted opening or hole for the insertion of a capillary tube and additionally providing for the attachment of a suction tube thereto.

These and other objects will be apparent from the drawing and the following description. Referring to the drawing:

FIG. 1 is a view of apparatus embodying the invention for collecting a sample of blood;

FIG. 2 is a sectional view on an enlarged scale of the fitting and adjacent portions of the collecting instrument or apparatus; and

FIG. 3 is a plan view of the fitting.

More particularly describing the invention, numeral 11 generally designates a plastic container known as a centrifuge tube or test tube in which a small quantity of blood is collected for test purposes. Numeral 12 designates a fitting embodying the invention which is adapted to be inserted in the mouth of the tube, and 14 designates a capillary tube which is removably received in the fitting. A flexible suction tube 15 is shown attached to the fitting and this may have a mouthpiece 16 at the end for convenience.

The test tube or centrifuge tube 11 is hollow being closed at its lower end and provided with a flange 17 at its upper end. The one shown in the drawing is the type used in micro-blood chemistry, being made of a plastics and having a capacity of only about 0.4 ml.

The fitting 12 is preferably formed of a resilient material, such as rubber or a suitable plastics, and it comprises a body 20 which is hollow and formed with a central portion 21 and a depending section or stem 22. The latter is cylindrical and may have a portion 23 to facilitate insertion of the stem into the upper end of the container 11. The body of the fitting also has a tubular laterally extending portion 25 which is shown as cylindrical and this accommodates the flexible section tube 15.

Internally the fitting has two intersecting bores 27 and 28. In axial alignment with bore 28 is a small bore 31 to the exterior of the fitting. This passes through a boss 31 at the top of the body and is provided with a flared mouth to facilitate insertion of a standard capillary tube 14. The latter is pushed through the bore 30 sufliciently to project into the test tube. The capillary tube should fit reasonably tightly in the fitting so that it is gripped thereby.

In the operation or use of the instrument a fitting 12 is inserted in the end of a test tube 11 in which it is desired to collect a sample of blood and assuming that the suction hose 15 is attached, a capillary tube is inserted through the bores 30 and 28 and caused to extend substantially all the way into the test tube 11. Then by applying the outer end of the capillary tube to a droplet of blood and applying suction to the tube 15 the blood of the droplet is drawn through the tube 14 into the tube 11. In this connection it should be noted that by reason of bore 28 being larger than the diameter of the capillary tube, there is open communication through the fitting from the suction tube to the test tube.

Although I have illustrated and described a preferred form of my invention, 1 contemplate that various changes and modifications can be made therein without departing from the invention, the scope of which is indicated by the following claim.

I claim:

Means for collecting a small sample of blood, comprising an elongated container open at one end, a fitting formed of a resilient material and having a stem removably received in the upper end of said container, said fitting being hollow and having a lateral tubular extension, a suction tube removably attached to said extension, said fitting having a small opening for grippingly receiving a capillary tube and so oriented as to register axially with said stem whereby a tube therein can extend from the exterior of said fitting into the interior of said container, and a capillary tube removably inserted in said small opening of said fitting and extending through the fitting into said container, said fitting providing an open passage between the interior of said container and said suction tube.

References Cited by the Examiner UNlTED STATES PATENTS 2,584,397 2/52 Pitman Q3259 X 2,697,945 12/54 Dovas 73-4256 2,941,869 6/60 Brown et al 734'25.6 X

RICHARD C. QUEISSER, Primary Examiner.

ROBERT L. EVANS, Examiner. 

